With the biggest decision of his career in the balance, Lyor Cohen went snowmobiling.

It was from a hotel in Jackson Hole, Wyo., on Jan. 24 – after public relations execs in New York had already drafted a press release – that Cohen finally made the decision to jump from Island Def Jam Records, which he built into the most successful hip-hop label in the industry, to Warner Music and his former boss, Edgar Bronfman Jr.

It ended almost two months of soul-searching for Cohen, and his move surprised many of his industry colleagues who couldn’t imagine Cohen not associated with IDJ and the artists such as Jay-Z and Ja Rule, whose careers were so intertwined with him.

In the end, Bronfman wanted him more, Cohen said. Universal Music, a unit of French conglomerate Vivendi and owner of IDJ, didn’t come to him to begin discussing a new deal until around Thanksgiving, a little more than a month before his contract ran out.

Vivendi, he said, did not support him during last year’s highly publicized lawsuit with indie label TVT, having refused to indemnify him until the judgment against him personally was reduced to $3 million from $56 million.

Another factor in his decision was the recent sale of Phat Farm, the fashion empire he co-founded with hip-hop impresario Russell Simmons for $130 million, of which Cohen’s take was about $20 million. Flush with cash, he felt willing to take a big risk, he said.

After meetings at Bronfman’s Upper East side home during December, Cohen turned him down on Dec. 26, but it was a New Year’s Eve call from Bronfman that got the talks jump-started again. To keep things secret and prevent leaks, he didn’t use his usual lawyer – music industry big shot Allen Grubman – but instead used a non-music-industry attorney.

“Even though Def Jam was part of my life for so long,” he said, “it was time to go to the next chapter. One of the primary reasons I made the decision to go to Warner was that it was purchased by people who want to be in the music business,” referring to the private equity group led by Bronfman. “You think [Bertelsmann] wants to be in the music business? Sony? Vivendi?”

Cohen, who is said to have nabbed a five-year deal plus an equity stake in the company, will become CEO of Warner’s U.S. recorded-music division once the sale closes, which is expected by mid-February.

The Bronfman team is hoping to slice $200 million to $300 million in annual costs from the business.

“I think Lyor knows how to connect with artists and sell records better than anyone in the business,” said Rick Rubin, a music producer who was a co-founder of Def Jam.

Cohen is most associated with rap – early on in his career he was the road manager for Run DMC – but has also nurtured the careers of such rock bands as Bon Jovi and the Red Hot Chili Peppers.

In 1988 he became president of Def Jam, a label founded in 1985 by Simmons and Rubin.

In 1994, Cohen and Simmons sold half of Def Jam to Polygram for $33 million – a deal that was negotiated by current Warner Music boss Roger Ames, who was then at Polygram. Later, after Polygram was sold to Bronfman’s Seagram, Simmons and Cohen sold the second half for $130 million.